Are Q waves normal in inferior leads?
Q waves are normally seen in the inferior and left lateral precordial leads in pediatric patients. The duration of these Q waves is almost always less than 20 ms. The amplitude can be rather large (up to 14 mm)7, especially in infants.
What is inferior Q waves?
Abnormal inferior Q waves may be the remnants of a previously unsuspected myocardial infarction. • We evaluated the diagnostic accuracy of electrocardiogram during inspiration and echocardiography. • Magnetic resonance is the gold standard method to detect myocardial infarction.
What causes abnormal inferior Q waves?
Background: Abnormal Q waves (AQW) in the electrocardiogram are commonly ascribed to underlying myocardial infarction (MI). As an imperfectly specific sign of MI, the usefulness of AQW in identifying MI depends on its incidence in the population studied.
What causes Q waves on ECG?
Technically, a Q wave indicates that the net direction of early ventricular depolarization (QRS) electrical forces projects toward the negative pole of the lead axis in question. Although prominent Q waves are a characteristic finding in myocardial infarction, they can also be seen in a number of noninfarct settings.
What does Q represent on ECG?
Electrocardiogram Interpretation Q waves represent the initial phase of ventricular depolarization. They are pathologic if they are abnormally wide (>0.2 second) or abnormally deep (>5 mm). Q waves that are pathologically deep but not wide are often indicators of ventricular hypertrophy.
What would be expected when evaluating an ECG for an inferior infarction?
Upon ECG analysis, inferior STEMI displays ST-elevation in leads II, III, and aVF. There are subtle differences in the ECG pattern depending on the artery occluded. Reciprocal changes (ST-segment depression) may be seen in lead aVL [6].
How is inferior stemi treated?
STEMI patients who present within 12 hours of symptom onset should receive treatment to try and open up the blockage known as reperfusion. This can either be by clot busting drugs given through the veins or by a procedure known as balloon angioplasty and stent placement (PCI).
What causes Q waves?
The usual cause of Q wave irregularities is a previous heart attack (MI – myocardial infarction) resulting in dead heart muscle tissue or thickening of the heart muscle possibly from insufficient blood flow to the heart.
What is a normal Q wave?
Origin of the Q Wave. The Q wave represents the normal left-to-right depolarisation of the interventricular septum. Small ‘septal’ Q waves are typically seen in the left-sided leads (I, aVL, V5 and V6)
What is borderline inferior Q waves?
Inferior q waves on ECG indicate possible prior inferior wall myocardial infarction (heart attack). To be significant, the q wave must be at least 25% or more in amplitude compared to following r wave, and be 1 mm wide. If it does not meet these criteria, it is a “borderline” q wave, and is less likely to indicate a prior heart attack.
What is borderline inferior Q wave mean?
It is sort of the firing pin for the main contraction of the heart (the tall upward blip on the EKG called the R wave). It shouldn’t appear in any significance on some leads. A borderline Q wave means that there is abnormal signal conduction through the heart due to a previous heart attack, or it may be a normal variant for an individual.